MC13135 single narrowband FM receiver circuit works and its application circuit


                                        MC13135 to typical application circuit2014-02-08_091545

The internal oscillation circuit and the external components MC13135 Pin1 and Pin2 of the vibration level of the composition of a first carrier frequency by the RF input signal from the selected frequency of the LC resonance circuit of MC13135 Pin22 input inside the first mixer stage for mixing , and the difference frequency 10.7MHz first IF signal from the Pin20 output by 10.7 ceramic filters to the selected frequency pin18 internally by the second mixer circuit . Internal oscillator circuit and Pin5 and Pin6 external crystal and capacitors constitute the second stage of the oscillation frequency of a selected lower than the first intermediate frequency ( ie frequency 455kHz) of 10.245MHz. 10.7MHz first IF signal with the second local oscillator frequency mixing, difference frequency which is :10.700-10 .245 = 0.455MHz, i.e. the second intermediate frequency signal is 455kHz .

The second IF signal output from the Pin7 from 455kHz ceramic filters selected frequency , and then into the MC13135 Pin9 limiting amplifier for high- gain amplifier , limiting amplifier stage is the main gain stage of the entire circuit . Pin13 external LC resonant element consisting 455kHz frequency discriminator circuit , the second intermediate frequency signal amplified by the frequency discriminator internally demodulation, and after the voltage level of the audio output of the audio signal amplified by Pin17 .

MC13135 is also equipped with an internal data signal amplification stage , Pin12 the RSSI input terminal , Pin15 to the input of an operational amplifier stage , Pin16 the RSSI output of the buffer amplifier . Pin10 and Pin11 of decoupling capacitors to ensure that the circuit stably.


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3 Responses

  1. mid 2014/02/28 at 21:58:46

    excuse me, do u offer some power supplys? mine is broken

  2. 2020/04/27 at 16:10:24

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